nav {
  background: #ccc;
  height: 50px;
}

.clearfix:after {
  content: '';
  display: block;
  clear: both;
}

#banner {
  background: rgba(0, 0, 0, 0.2);
  height: 700px;
}

header {
  background: rgba(0, 0, 0, 0.4);
}

nav ul {
  list-style: none;
  margin: 0;
  float: right;
}

nav ul li,
nav .logo {
  display: inline-block;
  line-height: 50px;
  margin-right: 20px;
}

nav ul li a {
  line-height: 50px;
  text-decoration: none;
  display: inline-block;
  height: inherit;
  color: #FFF
}

nav .logo {
  float: left;
  padding-left: 10px;
}

nav .logo a {
  text-decoration: none
}

#banner .inner {
  max-width: 300px;
  text-align: center;
  margin: 0 auto;
  position: relative;
  top: 160px;
}

#banner .inner h1 {
  margin: 0;
}

button {
  border: none;
  background: #333;
  color: #EEE;
  padding: 10px;
}

#banner button {
  padding: 14px 40px;
}

#banner .inner .more {
  margin-top: 280px;
}

.sub-heading {
  line-height: 30px;
  margin: 30px 0;
}

.logo {
  font-size: 20px;
  font-weight: 700;
  letter-spacing: 1px;
}

.logo a {
  color: #FFF
}

.wrapper {
  max-width: 1080px;
  margin: 0 auto;
}

.green-section {
  text-align: center;
  background: #089Db0;
  color: #FFF;
  padding: 100px 0;
}

.hr {
  width: 100%;
  height: 2px;
  margin: 20px auto;
}

.green-section .hr {
  background: #078494;
  width: 60%;
}

.sub-heading {
  font-size: 18px;
}

.green-section .icon-group .icon {
  display: inline-block;
  width: 80px;
  height: 80px;
  transform: rotate(45deg);
  margin: 20px;
  background: #0d6f7c;
}

.green-section .icon-group {
  margin-top: 60px;
}

.gray-section {
  background: #252f34;
  color: #FFF;
}

.gray-section .img-section {
  width: 45%;
  font-size: 0;
}

.img-section img {
  width: 100%;
}

.gray-section .text-section {
  width: 55%;
  position: relative;
  top: 67px;
  left: 50px;
}

.article-preview:after {
  content: '';
  display: block;
  clear: both;
}

.text-section h2 {
  margin-bottom: 20px;
}

.article-preview>div {
  float: left;
}

.text-section p {
  font-size: 18px;
  letter-spacing: 1px;
}

.text-section .sub-heading {
  font-size: 22px;
  margin-top: 0;
}

.text-section>* {
  max-width: 90%;
}

.article-preview:nth-child(odd) {
  background-color: rgba(255, 255, 255, 0.05);
}

.purple-section {
  padding: 80px;
  background: #3f3965;
  color: #FFF;
}

.purple-section h2 {
  -webkit-margin-before: 0
}

.purple-section .heading-wrapper {
  text-align: center;
}

.purple-section .heading-wrapper .hr {
  background: #373259;
  width: 60%
}

.card {
  float: left;
  width: 50%;
  min-height: 300px;
  padding: 50px;
  box-sizing: border-box;
}

h3 {
  font-size: 30px;
}

p {
  font-size: 18px;
  letter-spacing: 1px;
}

.card p {
  font-size: 18px;
  letter-spacing: 1px;
}

.card:first-child {
  background: rgba(0, 0, 0, 0.04);
}

.card:nth-child(2) {
  background: rgba(0, 0, 0, 0.08);
}

.card:nth-child(3) {
  background: rgba(0, 0, 0, 0.12);
}

.card:nth-child(4) {
  background: rgba(0, 0, 0, 0.16);
}

footer {
  background: #333;
  color: #FFF;
  min-height: 150px;
  text-align: center;
}

ul.share-group {
  display: block;
  width: 1080px;
  margin: 0 auto;
  padding: 30px;
}

.share-group li {
  display: inline-block;
  padding: 10px;
}

.copy {
  padding-bottom: 20px;
}

.main-wrapper {
  background: #444 url(./img/banner.jpg);
  background-attachment: fixed;
  background-repeat: no-repeat;
  background-size: cover;
  background-position: center center;
  overflow: hidden;
}

.mask {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.3);
}

#sidebar {
  position: fixed;
  top: 0;
  right: -300px;
  bottom: 0;
  width: 300px;
  background: #333;
  color: #FFF;
  padding: 20px 0;
  transition: right .5s 
}

#sidebar ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

a {
  color: #FFF;
  text-decoration: none;
}

#sidebar ul a {
  width: 100%;
  padding: 10px 30px;
  display: inline-block
}

#sidebar ul a:hover {
  background: #444;
}

.back-to-top{
  position: fixed;
  bottom: 30px;
  right: 30px;
  border:1px solid #888;
   
}